Most LED lamps with the prior art are fixedly mounted to the fixtures. If luminance and illuminant color are required to be changed or lighting direction is required to be adjusted, the LED lamp shall be replaced integrally, or illumination angle of the LED lamp shall be adjusted integrally, with complex operation and high replacement cost.
As to the prior art, there is also an LED illumination device comprising more than 2 LED illumination modules, which are electrically connected in groups. Via a cycle control switch or several independent switches, LED illumination modules are lightened up by various ways of combination, so as to achieve the effect of adjusting luminance or illuminant color. The said cycle control switch refers to a switching element respectively connected to multiple groups of load, enabling each group of load to start operation in sequence by controlling on-off action continuously. However, for the aforesaid LED illumination device with the prior art, on-off operation is complicated, combination of the LED illumination modules is singular; moreover, LED illumination modules can only be adjusted by means of re-connection of wires, which is complicated and unsafe, and shall be carried out by professionals, bringing inconvenience for users.